The present invention relates generally to plastic film wrapping apparatus for wrapping palletized loads or products, and more particularly to a new and improved plastic film wrapping apparatus or system which is portable, relatively simple in structure, and readily enables the manually controlled wrapping of palletized loads or products with plastic wrapping film while ensuring a high degree of safety for operator personnel.
As has been noted within previously filed U.S. patent application Ser. No. 09/432,284, which was filed on Nov. 2, 1999 and in the name of Hugh J. Zentmyer et al. for an APPARATUS AND METHOD FOR MANUALLY APPLYING STRETCH FILM TO PALLETIZED PRODUCTS, it is a known fact that approximately fifty percent (50%) of all stretch film that is manufactured is applied to, for example, palletized loads or products by manual means. It is also known that when applying such stretch film to, for example, palletized loads or products, the manner in which such stretch film is manually applied to such loads or products usually comprises either one of two methods. In accordance with a first one of such manual methods, as illustrated, for example, within U.S. Pat. No. 5,398,884 which issued to Stanford on Mar. 21, 1995, the operator respectively inserts four fingers of each hand into each one of two oppositely disposed recessed portions defined within the film core end caps so as to effectively hold or grasp the film roll, and while placing his thumbs upon outside surface portions of the film roll, so as to effectively cause a predetermined amount of back tension to be applied to the film whereby the film is effectively stretched as the film is being unrolled or dispensed from the film roll, the operator walks around the palletized load or product. In accordance with a second one of such manual methods of applying a stretch film to such palletized loads or products, as illustrated, for example, within U.S. Pat. No. 5,458,841 which issued to Shirrell on Oct. 17, 1995, and in lieu of directly holding or grasping the film roll, the operator holds or grasps a film roll dispensing or holding device which has a built-in tensioning mechanism. In accordance with either one of the aforenoted modes, methods, or manners in which stretch film is applied manually to the palletized products or loads, several operational drawbacks or disadvantages common to both methods or modes were apparent. Firstly, for example, the film roll, or the film roll and film roll dispensing or holding device, must be supported by the operator personnel, and yet the film roll and the film roll dispensing or holding device are quite heavy and cumbersome. In addition, in order to fully wrap a palletized load, the operator must bend down while holding the film roll, or the film roll and film roll dispensing or holding device, in order to wrap the film around the lower extremity portions of the palletized loads or products. Such requirements upon the operator personnel have been noted to cause acute discomfort, fatigue, and stress-related injuries. In addition, the operators experience fatigue and discomfort even when the operators are wrapping the upper regions of the palletized loads or products due to the continuous need for supporting the entire weight of the film roll, or the film roll and film roll dispensing or holding device.
A need therefore existed in the art for an apparatus, and for a method of operating the same, for overcoming the various operational disadvantages or drawbacks characteristic of the known PRIOR ART systems as briefly discussed hereinbefore and as disclosed within the aforenoted patents, and this need was substantially met by means of the apparatus or system, and the method of operating the same, which has been disclosed within the aforenoted U.S. patent application Ser. No. 09/432,284 and which has been quite commercially successful. However, while it has been noted in such aforenoted patent application that the apparatus or system disclosed within the aforenoted U.S. patent application Ser. No. 09/432,284 is portable in that the same is mounted upon a platform which has wheels, rollers, or the like so as to render the same movable or mobile, the apparatus is nevertheless relatively large and not readily transportable so as to, in turn, not be readily or easily movable within a particular wrapping plant or facility, or even yet further, readily or easily transportable between different wrapping plants or facilities located at different production sites.
Accordingly, the film wrapping apparatus or system disclosed within the aforenoted U.S. patent application Ser. No. 09/814,861 filed on Mar. 23, 2001 in the name of Gale W. Huson et al. for a PORTABLE FILM WRAPPING SYSTEM sought to overcome the various operational disadvantages of the known PRIOR ART and in fact successfully did so. Further improvements to such system were deemed necessary, however, in order to render such system simpler in structure, and accordingly, such improvements were in fact developed and accordingly disclosed within the aforenoted U.S. patent application Ser. No. 09/947,364 which was filed on Sep. 7, 2001 in the name of Gale W. Huson et al. and entitled PORTABLE PLASTIC FILM WRAPPING SYSTEM. While the apparatus or system as disclosed within the patent application Ser. No. 09/947,364 has operated quite satisfactorily, it has been determined still further, however, that additional improvements might optimally be incorporated within such a system in order to render the same essentially failsafe with respect to operational safety aspects for operator personnel. Occupational Safety and Health Administration (OSHA) regulations are continuously seeking to improve and ensure the occupational safety of manufacturing workplace environments in order to in fact protect operator personnel, and in accordance with the broad objectives of such regulations, it has been determined that a further need exists in the art for a new and improved film wrapping apparatus wherein the film wrapping apparatus is truly portable, transportable, simple in structure, and in effect comprises redundant safety mechanisms so as to readily enable the manual wrapping of palletized loads or products with wrapping film at a particular location within a production facility, so as to readily enable the manual wrapping of palletized loads or products with wrapping film at different locations within a particular production facility, so as to readily enable the manual wrapping of palletized loads or products with wrapping film at different production facilities, and wherein the film wrapping apparatus is relatively simple in structure and yet capable of ensuring a safe operational mode for operator personnel.
Accordingly, it is an object of the present invention to provide a new and improved apparatus or system for applying wrapping or packaging film to palletized loads or products.
Another object of the present invention is to provide a new and improved apparatus or system for applying wrapping or packaging film to palletized loads or products wherein the various operational drawbacks and disadvantages, characteristic of PRIOR ART apparatus, systems, or methods of operating the same, are overcome.
An additional object of the present invention is to provide a new and improved apparatus or system for applying wrapping or packaging film to palletized loads or products wherein the wrapping or packaging film can be applied to or wrapped around the palletized loads or products by means of operator personnel who can simply walk around the pallet upon which the loads or products are disposed and simultaneously push or guide the roll of wrapping film around the palletized loads or products whereby the palletized loads or products are accordingly packaged or wrapped within such wrapping film.
A further object of the present invention is to provide a new and improved apparatus or system for applying wrapping or packaging film to palletized loads or products wherein the wrapping or packaging film can be applied to or wrapped around the entire vertical extent of the palletized loads or products by means of operator personnel who need not support the weight of the film roll, or the film roll and the film roll dispensing mechanism, and in addition need not bend down in order to wrap or apply the stretch film upon or to the lower extremity portions of the palletized loads or products.
A still yet further object of the present invention is to provide a new and improved apparatus or system for applying wrapping or packaging film to palletized loads or products wherein the film wrapping apparatus or system is truly portable and transportable so as to readily enable the manual wrapping of palletized loads or products with packaging or wrapping film at a particular location within a production facility, so as to readily enable the manual wrapping of palletized loads or products with packaging or wrapping film at different locations within a particular production facility, or so as to readily enable the manual wrapping of palletized loads or products with packaging or wrapping film at different production facilities.
A last object of the present invention is to provide a new and improved apparatus or system for applying wrapping or packaging film to palletized loads or products wherein the film wrapping apparatus or system is relatively simple in structure, economical to manufacture, and exhibits redundant safety mechanisms for operator personnel.
The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved apparatus or system, for applying packaging film to palletized loads or products disposed at a wrapping station or location, which comprises in effect, a manually movable cart which is formed by means of a chassis wherein a pair of relatively large non-pivotal or non-caster type wheels are mounted upon a rear end portion of the chassis, while a pair of relatively small pivotal or caster-type wheels are mounted upon a front end portion of the chassis so as to permit the cart to be steered. The chassis is also provided with a vertically upstanding mast member, and a film roll carriage, upon which a roll of plastic wrapping film is rotatably disposed so as to be capable of dispensing the plastic wrapping film therefrom, is movably mounted upon the mast member. A counterweight is operatively connected to the film roll carriage, through means of a suitable cable, so as to normally tend to elevate the film roll carriage and the roll of plastic wrapping film mounted thereon. The mast member is provided with a plurality of vertically spaced apertures, and the disposition of a spring-biased, dual-pin bracket system, pivotally mounted with respect to the individual apertures, is able to be controlled by means of a manually-operated cable and lever mechanism.
More particularly, when the lever is squeezed, in a manner similar to that of a hand-operated brake lever upon a bicycle, the cable causes a first end of the pivotally mounted bracket to be moved so as to effectively withdraw a first one of the two pins comprising the dual-pin system to be released from a particular one of the apertures of the mast member while the second end of the pivotally mounted bracket is moved so as to effectively cause the second one of the two pins comprising the dual-pin system to be moved toward the mast member in preparation for insertion within another one of the mast apertures. The film roll carriage, along with the roll of plastic wrapping or packaging film mounted thereon, will be elevated along the mast member under the influence of the downwardly moving counterweight so as to wrap the palletized load or product as the operator pushes the cart along a circular path around the palletized load or product, however, it can be appreciated that the elevation of the film roll carriage is incrementally limited by means of the dual-pin control system.
Accordingly, if continuous spiral wrapping of the palletized load or product is desired to be achieved, the operator simply needs to alternatively squeeze and release the lever so as to permit the film roll carriage to elevationally move upwardly along the mast member as determined by means of the dual-pin control system. Alternatively, if continuous concentric wrap-ping of the palletized load or product with the packaging or wrapping film at a particular elevational level is desired, which is known as reinforcing wrapping, the lever is simply released so as to permit the cable-controlled pin to enter a particular aperture located along the mast member. When such cable-controlled pin enters such aperture upon the mast member, further elevation of the film roll carriage, and the roll of wrapping film mounted thereon, is prevented. At the completion of a wrapping cycle or operation, the operator can manually release the cable-controlled pin independently of the cable-control mechanism such that both pins are effectively simultaneously retracted from their mast apertures thereby permitting the carriage assembly to be lowered to its lowermost position in preparation for a new palletized load or product packaging or wrapping cycle or operation. It can therefore be appreciated that as a result of the alter-natively actuated dual-pin control system, redundant safety is inherently incorporated within the system.